diff --git a/src/uk/org/gss_data/pmd_drafter/api/ApiUtils.groovy b/src/uk/org/gss_data/pmd_drafter/api/ApiUtils.groovy
index 50cd8f6..e8e91df 100644
--- a/src/uk/org/gss_data/pmd_drafter/api/ApiUtils.groovy
+++ b/src/uk/org/gss_data/pmd_drafter/api/ApiUtils.groovy
@@ -12,7 +12,7 @@
         def (url, uriPath) = buildUrlAndUriPath(basePath, versionPath, resourcePath)
         println "url=$url uriPath=$uriPath"
         def http = new HTTPBuilder(url)
-        http.request( Method.valueOf(method), JSON ) {
+        http.request( Method.valueOf(method), JSON ) { req ->
             uri.path = uriPath
             uri.query = queryParams
             headers.Authorization = auth
diff --git a/src/uk/org/gss_data/pmd_drafter/api/DraftsetsApi.groovy b/src/uk/org/gss_data/pmd_drafter/api/DraftsetsApi.groovy
index f7925f7..35ff718 100644
--- a/src/uk/org/gss_data/pmd_drafter/api/DraftsetsApi.groovy
+++ b/src/uk/org/gss_data/pmd_drafter/api/DraftsetsApi.groovy
@@ -3,8 +3,7 @@
 import uk.org.gss_data.pmd_drafter.model.AsyncJob
 import uk.org.gss_data.pmd_drafter.model.Draftset
 
-@Mixin(ApiUtils)
-class DraftsetsApi {
+class DraftsetsApi extends ApiUtils {
     String basePath = "https://localhost/v1"
     String versionPath = "/api/v1"
     String auth = "Basic "
diff --git a/src/uk/org/gss_data/pmd_drafter/api/JobsApi.groovy b/src/uk/org/gss_data/pmd_drafter/api/JobsApi.groovy
index 46a72d1..7cf8be7 100644
--- a/src/uk/org/gss_data/pmd_drafter/api/JobsApi.groovy
+++ b/src/uk/org/gss_data/pmd_drafter/api/JobsApi.groovy
@@ -2,7 +2,6 @@
 
 import uk.org.gss_data.pmd_drafter.model.FinishedJob
 
-@Mixin(ApiUtils)
 class JobsApi {
     String basePath = "https://localhost/v1"
     String versionPath = "/api/v1"
diff --git a/src/uk/org/gss_data/pmd_drafter/api/MetadataApi.groovy b/src/uk/org/gss_data/pmd_drafter/api/MetadataApi.groovy
index ead79e6..892c5e4 100644
--- a/src/uk/org/gss_data/pmd_drafter/api/MetadataApi.groovy
+++ b/src/uk/org/gss_data/pmd_drafter/api/MetadataApi.groovy
@@ -2,7 +2,6 @@
 
 import uk.org.gss_data.pmd_drafter.model.Draftset
 
-@Mixin(ApiUtils)
 class MetadataApi {
     String basePath = "https://localhost/v1"
     String versionPath = "/api/v1"
diff --git a/src/uk/org/gss_data/pmd_drafter/api/QueryingApi.groovy b/src/uk/org/gss_data/pmd_drafter/api/QueryingApi.groovy
index d26c2cf..7eda07f 100644
--- a/src/uk/org/gss_data/pmd_drafter/api/QueryingApi.groovy
+++ b/src/uk/org/gss_data/pmd_drafter/api/QueryingApi.groovy
@@ -1,6 +1,5 @@
 package uk.org.gss_data.pmd_drafter.api
 
-@Mixin(ApiUtils)
 class QueryingApi {
     String basePath = "https://localhost/v1"
     String versionPath = "/api/v1"
diff --git a/src/uk/org/gss_data/pmd_drafter/api/SparqlEndpointsApi.groovy b/src/uk/org/gss_data/pmd_drafter/api/SparqlEndpointsApi.groovy
index 4ce1cb5..7d6e48d 100644
--- a/src/uk/org/gss_data/pmd_drafter/api/SparqlEndpointsApi.groovy
+++ b/src/uk/org/gss_data/pmd_drafter/api/SparqlEndpointsApi.groovy
@@ -1,6 +1,5 @@
 package uk.org.gss_data.pmd_drafter.api
 
-@Mixin(ApiUtils)
 class SparqlEndpointsApi {
     String basePath = "https://localhost/v1"
     String versionPath = "/api/v1"
diff --git a/src/uk/org/gss_data/pmd_drafter/api/UpdatingDataApi.groovy b/src/uk/org/gss_data/pmd_drafter/api/UpdatingDataApi.groovy
index 7eae024..ca07631 100644
--- a/src/uk/org/gss_data/pmd_drafter/api/UpdatingDataApi.groovy
+++ b/src/uk/org/gss_data/pmd_drafter/api/UpdatingDataApi.groovy
@@ -3,7 +3,6 @@
 import uk.org.gss_data.pmd_drafter.model.AsyncJob
 import uk.org.gss_data.pmd_drafter.model.Draftset
 
-@Mixin(ApiUtils)
 class UpdatingDataApi {
     String basePath = "https://localhost/v1"
     String versionPath = "/api/v1"
diff --git a/src/uk/org/gss_data/pmd_drafter/api/UsersApi.groovy b/src/uk/org/gss_data/pmd_drafter/api/UsersApi.groovy
index b5d97db..fb858fd 100644
--- a/src/uk/org/gss_data/pmd_drafter/api/UsersApi.groovy
+++ b/src/uk/org/gss_data/pmd_drafter/api/UsersApi.groovy
@@ -2,7 +2,6 @@
 
 import uk.org.gss_data.pmd_drafter.model.User
 
-@Mixin(ApiUtils)
 class UsersApi {
     String basePath = "https://localhost/v1"
     String versionPath = "/api/v1"